The present invention relates generally to pressure sensing devices, and particularly to a pressure transducer adapted for medical use.
It has long been known that pressure transducers used for monitoring blood pressure and the pressure of other body fluids or transducers that come into contact with biological fluids or materials must be intrinsically safe. That is to say, under no conditions can a high voltage be applied through such a body of fluid to a living body. Moreover, such transducers must be capable of being in a sterile condition immediately prior to use thereof.
In recent times it has been found advantageous to use a medical device only once and then to discard it, so as to prevent cross-contamination from one body to another. This implies the cost of such a device should be low enough to permit it being economically feasible to discard it after a single use. Therefore, it is an object of the present invention to provide such a pressure transducer.
A pressure sensing device suitable for medical use including: a dielectrically isolated sensor chip including a first wafer having first and second surfaces, a deflectable diaphragm formed therein and defining an active area of the sensor chip surrounded by an inactive area of the sensor chip, an electronic circuit formed on the first surface in the active area and being adapted to provide a signal indicative of an amount of deflection of the diaphragm, and a non-conductive coating on at least a portion of the second side; and, a plastic header including first and second ends, a recess in the first end and a plurality of electrically conductive pins extending from the recess through the header and out the second end; wherein, the sensor chip is secured within the recess of the plastic header such that the electronic circuit is in electrical contact with at least one of the pins.